s1 = [('b','A','15'),('c','B','12'),('e','B','10')]
s2 = sorted(s1, key=lambda s: s[2])
print(s2)
s3 = sorted(s1, key=lambda s: s[2], reverse=True)
print(s3)
s4 = sorted(s1, key=lambda s: s[1], reverse=True)
print(s4)
s5 = sorted(s1[1:3], key=lambda s: s[2])
print(s5)
